I'm doing a little research but I've run into trouble. The plants sold at PetSmart as an "Umbrella plant" lacks a scientific name and I've turned up a couple of different identity possibilities and they all have slightly different care.

Spathiphyllum wallisii/ peace lilly?
Cyperus alternifolius (not as likely, I think)

I'd like to know the proper care for it because right now I'm thinking a potted pond plant but I want to be sure.

Thank you!